CNBC is losing one of its biggest stars, Maria Bartiromo, when her contract expires on Nov. 24. By all accounts, she is headed to rival financial news channel Fox Business Network, and there are two basic ways of looking at the move: CNBC is letting its "Money Honey" go after 20 years to make room for new talent; or FBN just poached CNBC's top star, showing how serious it is about unseating its more popular business-news competitor.

From the statements released by CNBC and Bartiromo, the split seems amicable enough. Bartiromo's "contributions to CNBC are too numerous to list but we thank her for all of her hard work over the years and wish her the best," said CNBC. Bartiromo replied that "it's hard to sum up the gratitude and appreciation" she has for the CNBC team that gave her "a front row seat to some of the most important economic stories in the world" for two decades.

So perhaps both sides believe this parting of ways is in their best interest. But in the media, the dominant narrative is that Fox Business just scored a huge coup.

How far behind? "Last week, Fox Business averaged fewer than 10,000 viewers in the group that attracts advertisers, those between the ages of 25 and 54," says Bill Carter at The New York Times. "CNBC had more than three times as many with 31,000." Carter, for what it's worth, agrees with his peers: "The signing is a coup of sorts for Fox Business, which has struggled to establish a profile."

Fox Business Network has slowly built up its roster of stars, stealing Charlie Gasparino from CNBC in 2010 and Lou Dobbs away from CNN in 2011, as well as dipping into the talent pool at Fox News.

But "while CNBC certainly didn't have its best quarter," seeing its average daily viewership drop 29 percent in the 25-54 demographic, says Sam Thielman at AdWeek, "Fox Business dipped from a mere 14,000 demo viewers to 9,000 for the same period." Whatever her reasons for jumping ship, he adds, "the move to FBN won't increase Bartiromo's viewer base."

Bartiromo will also reportedly make appearances on Fox News, which will raise her profile considerably. But the $2-3 million question — her reported annual salary at CNBC — is whether Bartiromo can increase FBN's base by bringing a significant number of her fans with her. The Daily Beast's Lloyd Grove has his doubts:

Comparisons can be invidious, but by some estimates Lou Dobbs, her one-time boss when she was a greenhorn producer and assignment editor at CNN Business News, has been able to draw only seven percent of his CNN audience in the 25- to 54-year-old demographic since leaping to FBN in March 2011. Bartiromo — whom Dobbs notoriously advised against leaving CNN for CNBC in the early 1990s, saying it would be a serious career mistake — might or might not do better. [Daily Beast]

Another point of comparison is Erin Burnett, who jumped from CNBC to CNN in 2011. TV Newser's Chris Ariens checked in on Burnett in May 2012, eight months into her CNN tenure, and found a mixed bag. Burnett's ratings had been sliding for six months at that point — along with CNN's — but she was still drawing a larger monthly audience to her seven pm show (452,000 total viewers and 131,000 in the 25-54 group) than as CNBC's morning show host (283,000 total, 66,000 in the 25-54 group). That's not as great as it looks, Ariens adds:

CNN Erin is topping CNBC Erin, even doubling the demo. But take into consideration that CNN is available in more homes, seven pm (54 percent) has about double the HUT (homes using television) levels as nine am (29 percent), that CNN is a general interest news network and that CNBC's ratings don't include out-of-home viewers, and you get a sense of where things stand. [TV Newser]

In July, when Bartiromo was reportedly shopping herself around to FBN and CNN, an unidentified business news source told the New York Post that "it would be good news for Fox if she came over, but bad news for her." FBN's looser, debate-centric approach to TV was very different than CNBC's more orderly, scripted style, the source added.

Bartiromo's success at Fox Business Network may have less to do with her talents and adaptability than with the stock markets' health. A big reason FBN's and CNBC's ratings have been dropping is that the markets have been on a calm, upward trajectory. If things go haywire in the economy, that will be bad news for the U.S. but great news for Bartiromo's debut at FBN. Her former colleagues at CNBC would benefit, too, but in a crisis you want a trusted face explaining the news. That's where losing Bartiromo could really sting.